Mystery solved!
I checked my OOBs folder properties (size in bytes, and number of files) against a fresh install I have on my laptop, and there was a difference!
Turns out I accidently dropped two bmp image files (customized icons from the nearby Graphics folder) into my OOB folder, when I was copying them over to a flash drive.
That must have set off the warning.
Great new feature BTW
(it works
)
Thanks for the latest release Andy, and sorry for the false alarm.
Cross